Popularity and use of digital cameras and similar digital imaging devices (e.g., scanners) has increased in recent years as prices have fallen and image quality has improved. Among other things, digital cameras provide a user with an almost instantly viewable photographic image. Furthermore, digital cameras as well as scanners generally capture and store images in a native digital format. The native digital format may facilitate image distribution following an upload of the images from the digital camera to one or both of an archival storage and an image processing system such as a personal computer (PC). Similarly, once uploaded the digital images are easily stored for later retrieval.
However, concomitant with the rapid adoption and proliferation of digital photography, and more generally with the nearly universal acceptance and use of digital formats for archival image storage, has come an increased pressure on storage resources and media. In particular, image compression has become an important tool for dealing with storing and managing the vast amount of data associated with such digital images.
In general, image compression is performed one image at a time with each compressed image representing just a single image. Examples of commonly used, single image-based image compression include Joint Photographic Experts Group (JPEG) and JPEG 2000 compression standards. Another well-known, single image-based image compression technique is Lempel-Ziv-Welch (LZW) lossless data compression used to compress bitmap images using the Graphics Interchange Format (GIF). However, while efficient for producing compressed images, single image-based image compression may not produce the smallest or most compressed representation of a set of images, especially when the images are similar to one another. In particular, single image-based image compression simply cannot take advantage or otherwise exploit data redundancy that may exist in a set of similar images.
Certain embodiments of the present invention have other features that are one of in addition to and in lieu of the features illustrated in the above-referenced figures. These and other features of the invention are detailed below with reference to the preceding drawings.